1. Field of the Invention
The present invention relates generally to computer security, and more particularly but not exclusively to methods and apparatus for controlled sharing of media data.
2. Description of the Background Art
A public computer network, such as the Internet, encourages information exchange and collaboration among computer users. On the Internet, for example, Web 2.0, cloud computing, media sharing (e.g., Flickr™ website), and social networking (e.g., Facebook™ website), allow users to store media data on a public server computer for access by friends and other users. As a particular example, a user may store vacation photos on a photo sharing website for viewing by family members, friends, and colleagues. While public storage and access have undeniable benefits, a user loses control over his media data once it is published. In the photo sharing example, those who were given access to the photos can keep copies for further distribution to other people. Furthermore, when the user deletes his photos from the website, it is possible for the website to keep copies of the photos or not actually delete the photos from storage devices.